Question

Bài 3.Tìm x

a,24+3(5-x)=27

b, x : 4+12=23

c,(x-60):15=20

Answer 1

a,x=4        b;x=44      c;x=360  

hok tốt

Answer 2

a) \(24+3\left(5-x\right)=27\)

\(\Rightarrow3\left(5-x\right)=27-24\)

\(\Rightarrow3\left(5-x\right)=3\)

\(\Rightarrow5-x=3:3\)

\(\Rightarrow5-x=1\)

\(\Rightarrow x=5-1\)

\(\Rightarrow x=4\)

b) \(x:4+12=23\)

\(\Rightarrow x:4=23-12\)

\(\Rightarrow x:4=11\)

\(\Rightarrow x=11.4\)

\(\Rightarrow x=44\)

c) \(\left(x-60\right):15=20\)

\(\Rightarrow x-60=20.15\)

\(\Rightarrow x-60=300\)

\(\Rightarrow x=300+60\)

\(\Rightarrow x=360\)

Answer 3

\(a,24+3.\left(5-x\right)=27\)                                                \(b,x:4+12=23\)

\(\Rightarrow3.\left(5-x\right)=27-24\)                                              \(\Rightarrow x:4=23-12\)

\(\Rightarrow3.\left(5-x\right)=3\)                                                              \(\Rightarrow x:4=11\)

\(\Rightarrow\left(5-x\right)=3:3\)                                                              \(\Rightarrow x=4.11\)

\(\Rightarrow5-x=1\)                                                                          \(\Rightarrow x=44\)

\(\Rightarrow x=5-1\Rightarrow x=4\)

Answer 4

\(c,\left(x-60\right):15=20\)

\(\Rightarrow x-60=20.15\)

\(\Rightarrow x-60=300\)

\(\Rightarrow x=300+60\)

\(\Rightarrow x=360\)

Answer 5

a) \(24+3\left(5-x\right)=27\)

\(\Leftrightarrow15-3x=3\)

\(\Leftrightarrow-3x=12\)

\(\Leftrightarrow x=-4\)

b) \(x:4+12=23\)

\(\Leftrightarrow x:4=11\)

\(\Leftrightarrow x=\frac{11}{4}\)

c) \(\left(x-60\right):15=20\)

\(\Leftrightarrow x-60=300\)

\(\Leftrightarrow x=360\)

Answer 6

\(a,24+3\left(5-x\right)=27\)

\(3\left(5-x\right)=3\)

\(5-x=1\)

\(x=4\)

\(b,x:4+12=23\)

\(x:4=11\)

\(x=44\)

\(c,\left(x-60\right):15=20\)

\(x-60=300\)

\(x=360\)

Answer 7

a) 24+3(5-x)=27

=>15-3x=3

=>-3x=12

=>x=-4

b)x:4+12=23

=>x:4=11

=>x=11/4

c) (x-60):15=20

=>x-60=300

=>x=360